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sPHENIX is a new experiment under construction for the Relativistic Heavy Ion Collider at Brookhaven National Laboratory which will study the quark-gluon plasma to further the understanding of quantum chromodynamics (QCP) matter and interactions. A prototype of the sPHENIX electromagnetic calorimeter (EMCal) was tested at the Fermilab Test Beam Facility in Spring 2018 as experiment T-1044. The EMCal prototype corresponds to a solid angle of Δη × Δφ = 0.2 × 0.2 centered at pseudo-rapidity η = 1. The prototype consists of scintillating fibers embedded in a mix of tungsten powder and epoxy. The fibers project back approximately to the center of the sPHENIX detector, giving 2-D projectivity. The energy response of the EMCal prototype was studied as a function of position and input energy. The energy resolution of the EMCal prototype was obtained after applying a position-dependent energy correction and a beam profile correction. Two separate position-dependent corrections were considered. The EMCal energy resolution was found to be σ(E)/〈E〉 = 3.5(0.1) ⊕ 13.3(0.2)/√E based on the hodoscope position-dependent correction, and σ(E)/〈E〉 = 3.0(0.1) ⊕ 15.4(0.3)/√E based on the cluster position-dependent correction. These energy resolution results meet the requirements of the sPHENIX physics program. [ABSTRACT FROM AUTHOR]

The super Pioneering High Energy Nuclear Interaction eXperiment (sPHENIX) at the Relativistic Heavy Ion Collider will perform high-precision measurements of jets and heavy flavor observables for a wide selection of nuclear collision systems, elucidating the microscopic nature of strongly interacting matter ranging from nucleons to the strongly coupled quark–gluon plasma. A prototype of the sPHENIX calorimeter system was tested at the Fermilab Test Beam Facility as experiment T-1044 in the spring of 2016. The electromagnetic calorimeter (EMCal) prototype is composed of scintillating fibers embedded in a mixture of tungsten powder and epoxy. The hadronic calorimeter (HCal) prototype is composed of tilted steel plates alternating with the plastic scintillator. Results of the test beam reveal the energy resolution for electrons in the EMCal is $2.8\%\oplus 15.5\%/\sqrt {E}$ and the energy resolution for hadrons in the combined EMCal plus HCal system is $13.5\%\oplus 64.9\%/\sqrt {E}$. These results demonstrate that the performance of the proposed calorimeter system satisfies the sPHENIX specifications. [ABSTRACT FROM AUTHOR]

Open data and open source software might be part of the solution to sciences reproducibility crisis, but they are insufficient to guarantee reproducibility. Requiring minimal end-user expertise, the encapsulator system creates a time capsule with reproducible code in a self-contained computational environment. encapsulator provides end users with a fully featured desktop environment for reproducible research. [ABSTRACT FROM AUTHOR]

With the availability of powerful computational and communication systems, scientists now readily access large, complicated derived datasets and build on those results to produce, through further processing, yet other derived datasets of interest. The scientific processes used to create such datasets must be clearly documented so that scientists can evaluate their soundness, reproduce the results, and build upon them in responsible and appropriate ways. Here, we present the concept of an analytic web, which defines the scientific processes employed and details the exact application of those processes in creating derived datasets. The work described here is similar to work often referred to as "scientific workflow," but emphasizes the need for a semantically rich, rigorously defined process definition language. We illustrate the information that comprises an analytic web for a scientific process that measures and analyzes the flux of water through a forested watershed. This is a complex and demanding scientific process that illustrates the benefits of using a semantically rich, executable language for defining processes and for supporting automatic creation of process provenance metadata. Note to Practitioners-The Internet and associated computing capabilities have made it possible for scientists to derive novel datasets through complex processing of existing datasets that may be collected from many locations. But scientists rarely document dataset provenance . the set of processes and a description of how those processes were used - to allow derived datasets to be recreated. Enabling such recreation is an essential part of repeatable science, and thus it is imperative that any dataset generated by scientific computation include provenance metadata, documentation of the precise way in which that dataset was produced. Provenance metadata can help assure that scientists and others understand the value and limitations associated with using that data, but creating provenance metadata is a difficult and time-consuming problem. This paper describes an approach for helping scientists deal with the production and management of their datasets, including the automated generation of provenance metadata. The approach is based on the use of a precisely defined process definition language. The language is relatively clear and easy for scientists to understand, yet it is precise enough to support their control of the application of computing capabilities to the generation of datasets, and is also an aid to the management and understanding of these datasets. This paper illustrates these ideas by providing a case study of a specific problem in ecological dataset production and metadata provenance generation. [ABSTRACT FROM AUTHOR]